1. Field of the Invention
The present invention relates to a linear actuator for effecting reciprocating movement of a slide table along an axial direction of a cylinder main body by introducing a pressure fluid from fluid inlet/outlet ports.
2. Description of the Related Art
Heretofore, a linear actuator made up, for example, from a fluid pressure cylinder or the like has been used as a transport mechanism for various workpieces. The linear actuator serves to transport workpieces loaded and positioned on a slide table by reciprocal displacement of the slide table along a cylinder body.
As disclosed in the specification of Japanese Patent No. 3795968, the present applicant has proposed a linear actuator having ports for supply and discharge of pressurized air from a side surface of the cylinder main body, an adjuster that can adjust a displacement amount of the slide table, and a sensor groove in which a sensor capable of detecting the displacement amount of the slide table is installed.
With such a linear actuator, in order to use the actuator as desired, there are requests to vary the arrangement of the ports, the adjuster and the like, with respect to symmetrical side surfaces on the cylinder main body, corresponding to the use environment as well as the intended purpose of use thereof. In this case, another linear actuator is prepared having the ports, adjuster and the like provided on respective opposite side surfaces thereof, which is then exchanged with the original linear actuator. However, since it is necessary to prepare two types of linear actuators, equipment costs are increased, and in addition, since it is necessary to use only one of the linear actuators at a time, space is required for storage of the other linear actuator, thus making management thereof troublesome.
For solving such a problem, for example, as disclosed in Japanese Patent No. 3066317, a linear actuator is known in which ports, adjuster installation members, and sensor grooves are formed respectively beforehand with respect to both side surfaces of the cylinder body, thereby enabling either one to be used selectively, depending on the intended use or application of the linear actuator.
However, with the above conventional technique, since respective ports, sensor grooves for attachment of sensors, and installation members for adjusters are disposed respectively with respect to both side surfaces of the cylinder body, it is necessary to ensure that both side surfaces have a large size, and along therewith, the cylinder body becomes larger in scale. As a result, the overall linear actuator body itself becomes large in size.